26 Mar
2006
26 Mar
'06
9:57 a.m.
I've found a NiMH 6-cell pack that fits exactly in the recess of a
Semi-OT Laptop (HP OmniBook 800CT). (7.2v 3.3AH vs 2.6 AH)
My trollish question: would it be at all safe to let the laptop charge this?
The cell it replaces is LiIon which appears from my searches to be the
more fussy of the two technologies.
LiIon is _very_ touchy -- the cells are reputed to explode if you look at
them oddly. Well, perhaps not quite as bad as that, but you certainly
treat them with respsect.
NiMH is a lot easier to charge, a constant current supply will do. But
that doesn't mean that a LiIon charger is suitable, personally I'd not
use that.
Peripheral question. How does one set-up a constant current
circuit, being a non-electrical engineer?
The normal principle it to 'measure' the voltage across a resistorin
series with the load and to adjust some current control element of the
circuit until that voltage is correct (which means the current is correct
too, of course).
-tony